2N3055 Datasheet PDF – NPN Complementary power transistors

The devices are manufactured in planar technology with “base island” layout and are suitable for audio, power linear and switching applications.

The 2N3055 was designed for medium-current and high-power circuits. Commercially, it was used in many linear power supplies, audio amplifiers and low frequency power converters. It was second sourced by other manufacturers; Texas Instruments listed a single-diffused mesa version of the device in an August 1967 datasheet.One limitation was that its frequency response was rather low (typically the unity-gain frequency was 1 MHz).